Field of Invention
The field of this invention is control valves for fluid flow of gases, vapors, liquids and mixtures of these states. In particular, control valves of this invention are suitable for steam traps and are particularly effective in that use.
In the design, construction and operation of manufacturing, process and chemical plants, the control of fluid flow is a major concern to the design and operating engineer. It is also critical in environment heating and cooling systems. The size, shape and type of valves utilized at various control points results in a major cost of design and construction. In many applications it is desired to automatically control the flow of the fluid through a pipe, wherein the opening or closure action is effected directly by the temperature of the fluid flow being controlled. While one of the largest applications of this need is the steam trap, there are many additional uses for this type of control. For the purpose of clarification, the utility of the control valve of this invention will be described as it is applied to the steam trap application, but the control valves of this invention are not limited to that application.